1. The Field of the Invention
This invention relates to speaker system apparatus and more particularly to devices possessing omnidirectional sound dispersion characteristics.
2. Description of the Prior Art
The prior art abounds with apparatus utilized to disperse sound in varying directions.
U.S. Pat. No. 3,491,204 issued on Jan. 20, 1970 to S.A. Sherno teaches a sound system circuit and cabinet assembly employing a multi-channel stereo reproducing system having a center output channel derived from the two stereo channels. The stereo channels each has a plurality of speakers, and the derived center channel likewise has a plurality of speakers. The stereo reproducing speakers are mounted in vertically-pivoted enclosures. The center channel reproducing speakers are mounted in a fixed enclosure located between the vertically-pivoted stereo reproducing enclosures. The side vertically-pivoted enclosures each utilize a rectangular enclosure having a base speaker mounted on one vertical base thereof. The adjacent face, similarly disposed in a vertical plane is at right angles to the face bearing the base speaker and provides support for a mid-range speaker and a high frequency range speaker. The sound dispersion from each pivotable side enclosure is thus directed in a discrete pattern pivotably varied as the enclosure is rotated. This fact, coupled with the stationary sound dispersion characteristics of the center speaker baffle, produces an overall pattern which, though variable, is not truly omnidirectional.
U.S. Pat. No. 3,903,989 issued on Sep. 9, 1975 to B.B. Bauer discloses a loudspeaker system having a cabinet with two compartments, a first of which contains a low frequency loudspeaker for producing an omnidirectional radiation pattern, and a second compartment above the first, containing a rotationally adjustable vertically oriented baffle on which are supported additional loudspeakers motors designed to cover the mid-and high-frequency bands of the audio-frequency spectrum. The baffle is so shaped and the additional loudspeaker motors located in positions thereon that they operate as high efficiency gradient or dipole loudspeakers over a significant portion of their respective frequency ranges, whereby the directivity of the loudspeaker system can be controlled by adjustment of the position of the baffle relative to the cabinet. Since the stationary speaker produces a fixed acoustically directed pattern for the higher frequency components of the audible spectrum, a mixed pattern, dependent upon the frequency involved, is achieved.
All the prior art suffer the common deficiency in not disclosing a speaker apparatus, having a plurality of speakers, operated in discrete frequency bands, that are truly omnidirectional and substantially represent a dipole source of sound for all frequencies in the audio spectrum. Though a perfect point source for a sound apparatus, capable of handling all frequencies, is not currently available, the present invention provides an omnidirectional speaker apparatus possessing minimally two major lobes, oppositely directed, wherein each lobe is identical to its mate and covers a wide dispersion angle. The rotational ability of the baffle arrangement permits the lobes to be oriented at any angle desired.